Basic question regarding Maxwells distribution!

1. Jul 12, 2012

Rhydo

In a system of particles described by the maxwells boltzman distribution . What would be the fraction (Nv/V) of the total number of particles 'N' having the speed above the given speed 'Vo'?
I have been puzzling through this answer for quite a while. I' am knew to Quantum mechanics so can anyone explain to me the solution to this problem?

Any help would be appreciated!

2. Jul 12, 2012

mikeph

If Nv is normalised, you need to integrate Nv dv with limits of V0 to infinity. Or, just read off the values from the cumulative distribution function.

Equation (3) here: http://mathworld.wolfram.com/MaxwellDistribution.html gives you a formula for the fraction of particles slower than x, so the fraction that are faster would be one minus this answer, ie. 1 - D(V0). Probably good to do this one on a computer.

3. Jul 12, 2012

nonequilibrium

Also, the Maxwell distribution is not quantummechanical in nature, it is a part of classical mechanics (more precisely, it's a part of classical equilibrium statistical mechanics).